Formal:
* Taking everything into account
* In light of all the circumstances
* Given all the factors
* Considering all the variables
* Weighing all the evidence
* On balance
* Overall
Informal:
* All in all
* At the end of the day
* When you get down to it
* When all is said and done
* Taking everything into perspective
* In the grand scheme of things
* All things being equal
The best phrase to use will depend on the specific context and the tone you want to convey.